Fluid motor control



Nov. 3, 1953 Filed Nov. 4, 1944 E. E. LITTLEFIELD v FLUID MOTOR CONTROL 4 Sheets-Sheet 1 Fig.

INVENTOR.

1953 E. E. LITTLEFIELD 2,657,673

FLUID MOTOR CONTROL Filed Nov. 4, 1944 4 Sheets-Sheet 2 IIIII/IIIIIIIIIIIIIIIIIIIIIIA 86 8? Fig.6

Nov. 3, 1953 E. E. LITTLEFIELD 2,657,673

' FLUID MOTOR CONTROL Filed Nov. 4, 1944 4 Sheets-Sheet 3 Ill IN VEN TOR.

Nov. 3, 1953 E. E. LITTLE-FIELD FLUID MOTOR CONTROL Filed Nov. 4, 1944 4 Sheets-Sheet 4 3 m .g 23 w n i INVENTOR.

i afented Nov. 3, 1953 UNITED STAT FEUID MDBOR CONTROL Edgar: E. Littlefield, LosAngeles, Cali-f.

Appli'catibn Novemher' l, 1944;,Sierikl-N0. 5 62,0021

3 Q1aimsa (Cl. 121:4j.6.5).s:

This application contains subject matter com mon to my copending application-Number 465,995; filed- November 18, 1-942, now Patent Number 2,496,553, and to that extent is acontiriuati'on-in part ofthe earlier application:

The invention rel-ates to'improvements-:in=valvesand control systems; and" has partioularreference to fluid pressure operated: valves and valve sys; tems.

An object of the invention-is toprovide a-oom moncontrol-for-pressure-operated valves, as well asfor valves of other types; controlling the sup-- ply and-exhaust for a working piston;

beemployed in the control' ofitranslatingdevices; including such as those describedherein.

Fig. l'is avertical view: of a valve assembly, withparts-broken-away; showing-thenmain valves in locked position, the flow of: fluid being con--v trolledbymeans or the valvesicontrolling the passages: through the. main.- valves.

Fig: 8 is a verticalaview of a valve assembly,

partly; insecti'om of'a-furthenmodification.

Theinvention also relates to-fluid pressure op erated' valves each having a-pilot valve to -control exhaust valves andcommon actuating means therefor. 7

Another object is to improve the construction and-operation of fast opening valves, slow, closing-- valves, fluid: pressure: operated valves: and; electrically operated or controlled val-vesiof vari-a ous 'ty-pes.

Other objects and many of: the attendant ade vantages of' this invention will hereadily -apprea-a ciated 1 as t-hesame becomeshetter: understoodbv reference to the following detailed description when considered in connection: with. the accome panyingdrawings, wherein:

Fig. 1 is a vertical: sectional view through; a. valve assembly according: to the. present invene= tioni V Fig. 2- is=:a sectionaliviewl on line ZwZ-zOfLEigu L looking; inthe direction of the. arrows;

Fig. 3iv is a vertical sectionall view, Withi parts;v broken away, showing a modified; form, of: pilot: valve.

Fig. 4 is'an enlarged vertical. sect-ionali view: with parts broken awayv of: a further? modifica tion of I amain valve. V

Fig; 51s a schematical circuit. diagram illus-i tratingone manner of using the: valve assembly: ofFig. l.

Fig. Sis a schematicalwiring 'diagramthatmaw indicated-at- P2 jectsin neck H: can' be adjusted by means oi Fig; 9 is a control system employing features oi the valves: describedi herein.

Referringin detail tome-drawings; Fig; 1 il'- lustrates amainexhaust valve-- i; a main supply valvei both-of which are fluid-pressure operatedand-which are assembled with a common electrical actuating member: inthe'form of asolenoid 3. The valves rand-rand solenoidt are preferably" mounted together" to form a unitary struotu're;

The exhaust valve lhas an-= inlet 4 and anout'- let 5- andtherebetween avalve seat ehaving-=- above it' a valve head which carries a piston 8= sli-dableina chamber 9 the cap- Hr which is adjustablyscrew-threadedinthe neck I I as The distance that cap is: pro- Washers H, and similar adjustment is-possible with all othervalve caps shown. The piston-e-hasa comparativel y-smalkinlet passage I3 extending therethroug-h to admit fluid-under pressure front inlet 6 behindt-he piston 8 to-seat the-valve i: at certain-times. The-piston a: also hasaxial-1y thereth-rougha comparatively large drain passage I4; the upper-end of: whichforms a seat for the pilotvalve [5 carried by a: stem is which. slides:

inthepassage I l and which extends; below the bottomof the-valve head 1 asindicatedz at i755.

Ihe val-vesl= and 2 are-physically mou-nt'edto get-herbya tube l8 oi nonmagnetic material; the upper end of which issecured by screw threads Ill-in anope-ning iil -in the bottom Z l of the case ingofvalve L. The l oweuend of 'tlibe i8 sis con-i nected screw threadsifi in an opening 2%; in V nonmagnetic. material. which is screw threaded:

insideof tube; t8 Ari-annular. flangenr sh ulder on the lower: endg of; armature 29;: contacts; the lower, encloftube 318i limiting thezupward; travel;

aesaevs of the armature, which is urged upwardly by a compression spring 32. A set screw 31 placed in any desired position would serve the same purpose, and this could also be used for locking the armature against operation if for any reason it is desired to do so. Around the tube 18 and extending between the bottom H of valve l and the cap 24 of valve 2 is a solenoid 3. When solenoid 3 is energized, the armature 29 is moved towards the center of solenoid 3, against the action of spring 32, thereby retracting the push-rod 26 and allowing the valve stem I6 to descend and the valve to close.

The supply valve 2 has an inlet 33, and an outlet 34 and therebetween a valve seat 35 for a main valve head 36 mounted on a screw-threaded stem 31 which has at its upper end a piston 35 slidable in the chamber 39 in the cap 2%. The piston 38 has an axial drain passage 46 therethrough, the upper end ll of which serves as a reciprocable in the casing 33, of non-magnetic material. Casing 53 is secured by screw threads 24 in a bore in the top of piston 38. The pilot valve 42 at its upper end is provided with an ad justable abutment in the form of a screw 45, preferably of magnetizable material, against which bears a compression spring .6, the upper end of which bears against the top of pilot valve casing 33. The top of casing %3 has a threaded breather hole 41, which may, if desired, be closed by a small screw. The casing 23 and the piston 38 and valve 36, all of which are arranged in operative relation, are urged in a downward direction by spring 43 between the underside of wall and the top of a sliding armature it of magnetizable material, such as stainless iron, which rests on the top of casing 63, and which may, if desired, be provided with side openings at the bottom, for release of fluid. The side of casing 33 is provided with a port 56 so positioned that it will be uncovered when the valve 32 is raised against the 7 action of spring 48, due to energization of solenoid 3. Adjustable mounting of casing 63 permits adjustments to be made in the position of the port 56. Piston has an inlet passage 5! there: through, somewhat smaller than drain it, communicating with chamber 39. Port fill may be of any desired dimensions and may, if desired, be employed to regulate flow of fluid from chamber 39. The space provided for piston 38 and valve head 36 may easily be such that a piston and valve arrangement, such as 8 and T of valve 1, may be substituted therefor, if desired. In such case valve means 53 of Fig. 3 will be found a satisfactory means for controlling drain passage Hi. When solenoid 3 is de-energized, orwhen the device is disconnected from the supply and exhaust lines, as is the case in Fig. 1, the various parts are in the position shown in this figure.

Assuming that the device is properly connected for use, solenoid 3, when energized, will cause the armature 29 and pilot valve 32 to move toward the center of solenoid 3. Movement of armature 29 downwardly retracts push-rod 26 and compresses spring 32 permitting pilot valve !5 to close, whereby the pressure admitted through inlet passage i3 builds up on top of piston 3, causing it to close valve 1, or holding it closed, if it is already in the position shown in Fig. 1. When pilot valve 12 moves upwardly it uncovers valve seat ll and port 5%, permitting the pressure on top of piston 38 to be relieved faster than it is built up through the inlet passage 5 l, whereby the pressure on the under side of piston 38 overpowers the pressure on the top thereof, and the valve 35 moves to open position.

De-energizing of the solenoid permits fluid pressure, admitted from inlet 33 through passage 5! to chamber 39, to accumulate above piston 33, thus closing valve 35. Pilot valve is, of upper valve i, has now assumed an open position under action of the compression spring 32. When fluid is exhausted from the cylinder under pressure, the pressure on the underside of piston 8 will be greater than on its top because pressure will escape through drain passage Hi faster than it is built up in chamber 9 through passage i3, hence the valve i under these conditions will open.

If desired, the inlet 33 may be provided with a pivoted impact device or knocker 52 actuated by inrush of fluid to strike the underside of piston 38 and help it to rise. This or any other suitable impact device may be employed in connection with any of my valves, when desired, to aid in unseating the same.

In the modification shown in Fig. 3 the pilot valve 53 is similar in construction to that shown in my Patent 1,633,217. The needle valve 53, having a reduced diameter, comes opposite the port 5% when the pilot valve is in raised position, increasing the effectiveness of the valve.

In the modification in Fig. 4, the pilot valve 55 controls not only the axial drain passage 53, as before, but also the inlet passage 5? because the discharge end 58 thereof, as well as passage 56, communicate with chamber 85., which is in communication with the interior of the pilot valve casing 59. The shank of valve 55, being of a diameter which almost fills the inside of casing 59, the flow of fluid through passage 5'5, when the valve is closed, is restricted between the side of valve 55 and the inside of casing iii; in seeking an outlet through port 65 to reach chamber 6| above piston 62. When pilot valve 55 is in its raised position, its conical valve head 63 is withdrawn to a position above or adjacent port so that the former no longer restricts the discharge from chamber ti through port to drain passage 55. By thus controlling the fluid I provide the advantages of a quick opening and slow closing valve.

The flow through passage iii may be adjusted by screw plug Similar regulating means may be used in connection with the other valves, if desired. Washers and a threaded connection between the upper and lower parts of piston 5? enable certain adjustments to be made when desirable. A threaded connection between the piston E2 and valve head G l also makes certain adjustments possible, although the parts may be made integral if desired. An adjustable connection also permits the main valve to be locked in closed position when it is desired to employ the drain passage only for control of fluid, as may be the case in the control of a low pressure gas. Or a nut may be added to the threaded piston stem and tightened up on the port wall. A similar arrangement may be provided for the valve I, if desired. By this I mean that if the member i6 is removed and the threaded end of piston 5 extended far enough below the port wall to permit a nut of the proper size to be threaded thereon the piston may be locked in closed position on its seat 6. The lower end of the threaded piston extension being flat, the lower end of the drain passage will form a suitable seat for any or" the bysea-2 pass:- controlling members. For: instance; thesmaller: end of the-push-rod It may extendiup wardly into the piston, while the valve. end: l5;

may be arranged to cooperate with theseat at the lower end of the by-pass l4. Several other arrangements suggest themselves. The needle. valve of the member -42, for instance,.may.be arranged to cooperate with the lower: end of: by.-- pass M by substituting it for the member 2.9.x

Compression springs may, when. desirable;. be.

inserted. between the tops of; or all: of." the.

pistons and. the upper walls of the; honnetsfor the purpose of. urging the pistonsato. their seats.

In order to increase the effectiveness ofi'thedevice and enlarge itsscope of useiulnesathe: parts in numerous cases are assembled. adjustable;

and/ or interchangeablerelation.

Fig. 5 illustrates av diagram. of; connections.

which may be employed for. operating-a piston E5 in a cylinder 6.6-, although other'connections may be used. As here illustrated, the inlet; side 450i: exhaust valve 8 and the outletiside 34-ofthein1et valve 2 are connectedby pipes 67 and 68;.respectively, to the same end 69' of the cylinder 65,- while the other end iii of cylinder 66 is connected by pipes H and T2 in a similar manner to the inlet side l of exhaust valve l and to the outletside 2 5' of supply valve 2, respectively. Withsolenoid. 3 (lo-energized, namely, with the parts in. the position shown in Fig. 1, referring now'to Fig; 5, the end 6-9 of cylinder 66 can exhaust;throughv pipe 6'! and exhaust valve. I, so thatpiston. 653 is. free to move to the left. If solenoid; 3 isnowenergized, the exhaustvalve i is, closed and'the. supply valve 2 is opened, thereby admitting pressure to the right side of piston 6-5 .to .urgeitt to the left. Piston t5 can, of; course, be moved to the right, by energizing solenoid 3 While leaving. solenoid 3' ole-energized.

A circuit arrangement which may be used for solenoid 3 is indicated in Fig. 6 wherein linesv 73 and (4 lead to a suitable power supply. On side '14 is connected directly to solenoid 3', while the other side 13 is divided into branches 86 and 87; The branch 85 is connected through the switch. it to the other end of 13 adjacent-where it enters the solenoid; the other branch .81 is connectedto an adjustable contact it of a resistance coil TI, co-acting with a bimetallic element 19 ofthe thermo-relay device 8%], thence through the primary 78 of a step-down transformer or impedance 85, beyond which it: joins the line 13 lead-- ing to solenoid 3. If switch it is momentarily closed, with thermostat '59 in the-position shown in Fig. 6, a comparatively large starting current is supplied to solenoid 3, through lines 14, 13. and

branches 853 and 87. Since branch 37 isnormally' in closed circuitrelation with the currentlsupply, the current will continue to flow through transformer winding 78 after switch 15 is opened, subject to control by secondary circuit 8| which includes a normally closed'circuit controlling ele-' ment 82, for the bi-metallic element 7.9; The secondary circuit 3| also includes anadjustablerersistance or rheostat 83 by means of which the proper current may be providedfor holding the armatures, such as 29, 42, 49 and 55 in their operated position, less current being required'to hold the armatures in this position than is re-- quired'to move them to this position. Thecon- W tact BZ-may be of the adjustable screw type. By

reversing the iii-metallic element. on the screw connectiontfi, orv by. otherwise employing an-element that closes the circuit when heatis applied,

the element may be employed for delaying thepurposeof. adding. aLnutL thereto.

closingiofiavalve; or for continuingtheoperatiori.' of any other-device connected for. operation ina similar manner, for a:. predetermined: time. In." thiscase the contact would. be normally. open,. but when switch. T5 is..cl0sed. the-heat developed: inthe bi-metallicstrip. 19. will cause it to close: the circuit: and thus hold=the valve open until-. contact: 82-: opens; when the temperature of. the bi-metallic member: has; droppedzsuinciently;

the first: casezabove, i. e., when the contact. 82 is-normallyz closed ,1 thecircuit will open. after a. certain. temperature: rise in the bi-metallia-element, thus preventing overheating. or. the device, such: asasolenoidl 3.. The bi-metallic strip. may be: provided with. a. longitudinal; slot for adjustable; connection, with: screw connection. 89Li desired;

By; the. above. means, either.- separately" or to gether as: maybe; the. opening or'closing of contact: d2 may be controlled. according-to a..pr.ede:- termined time. limit. The adjustable contact 'llr. provides for control of. the heat applied to the biemetalli'c member 19. The; adjustable resist ance; orrheostat: 831 may be employed either'tolimit the. amount or current flowing in the pri-- mary. 18101 to open the secondary circuit, as, desired.

The abovemethodsof control maybe employed. in the control of many different types of; translating; devices besidesthose indicated.

Ohviously, the vfluid control, means I hav provided. may be. used, inconnection with hydraulic. control systems.

Detachablyassembling the valves, asin, Fig, 1;. permits separation and, independent employment; ofithe. same for'controlling such fluids as waterl. refrigerants, gas, air, oil, etc.

Where the fluid: to be controlled is of insufficient pressure to lift: the main valve. after the pilot valve: is. unseated, as would probably obtain in some cases, the. drain passage alone may be used and madesufiicientlylarge to meet the require-- ments; of. any particular case. Of course, the drain passages of any of the valves may be of any capacity requisite for any particular purpose..

The valve: l, shown in the upper part of-Fig. 1, may easily, be of: a type wherein a larger drain passage. is controlled by a plurality of auxiliary valves such as are-shown. in my Patent 2,070,607,

in. which; casethe, enlarged fluted upper end of the push,v rod 26' may, be omitted, permitting the same totelescope into the drain passage of the. mainvalve. The guide 3'1, shown in the, patent, may, if desired, be employed to cause an unseating of the smaller valve first.

Similar reference characters refer to similar parts.v

In Fig. 7 I showa, convenient arrangement, heretofore referred to, wherein the main valves may be lockedin closed position, as by the nuts indicated inthe. drawing, and. the flow of fluid controlled by; theauxiliaryvalves. While otherv elements found, in the drawings may be arrranged. to accomplish a-similar'purpose, in Fig. '7 I have employed the: structure: shown in Fig. i, for the lower valve, while in. the upper casing I. have sub.- stituted'. the. piston 33: for piston 8', since the former is already provided with a threaded extension, towhich. a. nut may be threaded and tightened'up onthe port wall, as shown. It haspreviouslybeen mentioned, however, that, if, de-- sired, the threadedtendof piston 3. may be ex.- tended to a. point below. the port wall for'the nutthaiiis: added;..the.lower. valve. is. substantially Except for the assists ,7 a counterpart of the valve of Fig. 4. The needle valve of the upper combination may be any of those shown, such as either 55 or 42. As shown, it is inverted, so that the needle valve end may co-operate with the seat formed by the lower end of the by-pass it. In like manner, any suitable one of the compression springs shown, such as 22, may be employed to cause the needle valve to seat when solenoid S is ole-energized. Tube 3%? has been omitted, but it may be added, if desired. In the upper arrangement the flow of fluid is pref erably from A to B, while in the lower valve it is in the direction of the arrow. Other connections may, however, be made. According to the present showing, when solenoid 3 is energized, needle valves 55, preferably made of stainless iron or its equivalent, are retracted toward the wall 25, permitting fluid to flow through passages it and 55. I have previously stated that the drain passages may be of any required size. When solenoid 3 is de-energized, the co-operating compression springs urge the valves to their seats. Removal of nut 55. engaging the lower end of duct member would form a combination in which the operation or" the upper valve member would be dependent entirely upon electrical energy while the lower main valve would be fluid-operated and pilot-controlled.

in the modification shown in Fig. 8 I have, for illustrative purposes, and as a matter of convenience, shown the details of construction as housed in the framework of the arrangement shown in Fig. l, certain elements shown in that figure having obviously been omitted in order to show the modified arrangement. In the port wall I have screw threaded a plug i having a sage 532 therethrough, the lower end of which forms a seat for a needle valve es. Slidable on the non-magnetic stem t l of the needl valve is a magnetizable sleeve 35 constituting an armature. The lower end or" the member St is provided with a cap it and etween this cap and the lower end of sleeve a compression spring ti acts to urge the sleeve to assume a position against the shoulder til of the needle valve 93. The needle valve itself is urged to a seated position by the compression spring 22 mounted between the wall 25 and the cap or head 9% of the needle valve stem. The sleeve 85 is preferably made of stainless iron or its equival nt. The pointed end of the needle valve if desired, be made of stainless iron and mounted on the non-magnetic stem 9 in any convenient manner. The cap or head 96, also, if desired, be made of stainless iron mounted on the stem lit in any convenient manner.

The lower valve housing 2 is provided with a plug t9, sir ilar to the one of the upper valve, screw threaded into the port wall lilfi. Like the former, this plug is also provided with a passage iiii. The upper end of this passage forms a seat for a needle valve having a non-magnetiaable stem iii; provided with a cap or head tilt. Slidable on the stem tilt is an armature Hi5 preferably madeof stainless iron or its equivalent. If desired, a compression spring, such as may be interposed between the sleeve 55 and the cap or head lhe stem the, together with the cap i and needle valve end, may be made of brass simi ar material, or the cap and/or valve end made of stainless iron, or its equivalent, all desired, to meet th requirements of any particular purpose. Between the wall 25 and the upper end of the valve stem is inserted a compression spring, such as t8, the lower end of which rests on a magnetizable plug Hi6 which, in turn, rests on the top of cap I64. In certain cases the use of this plug Hi6 would be optional. The plugs 9i and 99 may be identical in every respect and may, on occasions, and, if desired, be provided with fluid iiow regulating means, such as 5'5, Fig. 4, so that the flow through either or both of the passages through the plugs may be regulated. In this connection it may be desirable to have the exhaust passage, assuming for example that the valves connection is to a power cylinder, of greater capacity than the one handling the supply. I contemplate, that the valve assemblies in both the upper and lower chambers, i. e., the chambers above and below the wall 25, may be identical in every respect, or interchangeable, one for the other. For instance, the valve 93 and its co-operating parts may be substituted for the valve H32 and its co-operating parts or vice versa. Such an arrangement enables the units to be made in pairs, thus, in many cases, reducing manufacturing costs.

When solenoid 3 is energized the valves $3 and Hi2 are unseated and retracted toward the wall permitting fluid to flow through the discharge passages 92 and Edi, of the plugs 9i and Upon tie-energizing solenoid 3 the valves again assume a closed position, as indicated in the drawing.

In Fig. 9 I have shown a diagram of connections in which two valves of the above type, or similar (shown in conventional form), are connected to control the supply and exhaust for a power cylinhaving a piston Hi8, which may be connected in any convenient manner for operating any s'"itable mechanism. Supply pipes c and d connect the cylinder at each end with a source of fluid under pressure Hi9. Exhaust pipes f and it connected to the cylinder, as shown, permit fluid at times to exhaust from the cylinder. The valve assembly B, as shown, is connected so that its valve member may control the supply of fluid to the cylinder, at one end, and the valve member m connected so that it may control the exhaust from the opposite end of the cylinder. The valve assembly A is connected in a similar manner to the left end of the cylinder, or so that its valve member n may control the supply of fiuid to the left end of the cylinder and the valve member 0 so that it may control the exhaust from the right end of the cylinder. 1'" solenoid $3 is now energized, fluid under pressure will enter the cylinder through branch pipe 0, causing piston 538 to move to the left, tending to force fluid from the cylinder through exhaust pipe it. Since the energization of solenoid S has unseated both valve members m and 7c fluid will exhaust from the cylinder as indicated. If solenoid S is now deenergized and solenoid S energized fluid under pressure will enter the cylinder through branch pipe 61, causing the piston 88 to move to the right, tending to force fluid from the cylinder at the opposite, or right end, and since the energization of this solenoid has also unseated valve member 0, fluid will exhaust through the latter.

It is apparent that any or all of the improvements herein disclosed for one of the valves may be employed in the others. Also, that the main valves may be used separately or in various combinations and in many ways other than as herein illustrated. Also, that spring or gravity means may sometimes be used in returning the piston to the position previously occupied.

Etc-arrangements in the elements shown and described may be made for carrying out any particular or desired purpose.

A combination may be made up of a fluid operated valve, for instance, and one not fluid operated. For example, by removing the plug 99, Fig. 8, and the needle valve arrangement I05, the fluid operated valve assembly of either 64, Fig. 4, or 36, Fig. 1, may be substituted therefor. Or any other desired arrangement to effect the purpose may be employed.

For the sake of elearness and brevity I have illustrated only a few simple embodiments of my invention and the several features thereof, and have described them with particularity; but it will of course be understood that my invention is not limited to the forms thus illustrated, as I intend to cover all forms, methods, and arrangements that come within the definitions of my invention as set forth in the appended claims.

I claim:

1. In combination; a cylinder having a piston reciprocable therein; a valve assembly having two valve seats, two valves only, and common electrical controlling means therefor said means acting upon said valves to move the same relative to the said seats and relative to each other thereby controlling a supply of pressure fluid to the cylinder to cause the piston to move in one direction and controlling exhaust of fluid from the cylinder in response to movement of the piston; a second valve assembly having two valve seats,

two valves only, and common electrical controlling means therefor said means acting upon said valves to move the same relative to the said seats and relative to each other thereby controlling a supply of pressure fluid to the cylinder to cause the piston to move in an opposite direction and controlling exhaust of fluid from the cylinder in response to movement of the piston.

2. The combination With a piston, and housing means therefor, of a source of operating fluid; a pair of valves, one of which controls the admis sion of operating fluid to one side of the piston and the second of which controls exhaust of fluid from the path assumed by the piston, due to pressure of operating fluid; a second pair of valves,

one of which controls admission of operating fluid to another side of the piston and the second of which controls exhaust of fluid from the path assumed by the piston, due to the pressure of operating fluid; and common electrical means for the valves of each of said pairs of valves for causing the said valves of each pair to move along a common axis toward and away from each other to seat and unseat.

3. The combination with a piston, and housing means therefor, of a source of operating fluid; a pair of valves, one of which cooperates with said source to control the flow of said fluid, which assume unseated positions when they are moved toward a common point substantially within their paths thereby to drive said piston in one direction; a, second pair of valves which assume unseated positions when they are moved toward a common point substantially within their paths thereby to drive said piston in another direction; and common electrical controlling means for each pair of valves to control the movement of the valves of each pair toward and away from their said common point.

EDGAR E. LITTLEFIEID.

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